Black Friday is here! Take advantage of this unique opportunity and get up to 80% extra knowledge for free! Read more here
bf extended_2022

Lesson 12 - StreamAPI in Java - Modifying stream methods

In the previous lesson, StreamAPI in Java - Generating streams, we looked at ways to create general and numeric streams. In today's Java tutorial, we're going to learn about another methods, that modify streams.

Stream modification methods

Modification methods apply some rules to an existing stream and create a new one.

The filter() Method

The method's signature is as follows:

filter(Predicate<? super T> predicate)

As the name suggests, the method creates a new stream of elements that match specified criteria. Let's show the usage on an example:

    .of("Peter", "Michael", "Carl", "John", "Martin", "Jack")
    .filter(name -> name.startsWith("J"))

The result is all the names starting with the letter "J":

Console application

The distinct() Method

Let's start with the method signature again:


The method creates a stream of unique values from the original stream. To achieve the uniqueness, the values are compared internally using the


...End of the preview...
Continue further

You will gain knowledge worth hundreds of thousands for a few crowns

You've come here and that's great! We believe that the first lessons showed you something new and useful
Do you want to continue the course? Go to the premium section.

Limited offer: Learn all knowledge and save money

Buy lessons and exercise submitting one by one $7.20
Buy all currently available lessons with exercise submitting and other features for an exclusive price $1.44
Currently, you have $0
By buying this exclusive package, you'll have access to all 13 lessons in this course including exercise submitting while saving $5.76. This is a time limited offer for all lessons in this course. Buy it now and gain a limited 80% discount.
Buy only the lesson $0.90
Currently, you have $0

This article is licensed: Premium, by buying this article, you agree with the terms of use.

What will you get from us in the next lessons?
  • Unlimited and permanent access to individual lessons.
  • High quality IT knowledge.
  • Skills to help you get your dream and well-paid job.

Article description

Requested article covers this content:

In this Java tutorial, we'll learn about StreamAPI methods that modify existing streams and create new ones.

You gain credits by supporting our network. This is done by sending a helpful amount of money to support the site, or by creating content for the network.

Article has been written for you by Petr Štechmüller